Operating instructions

228 Cisco Systems Intelligent Gigabit Ethernet Switch Module
drivers necessary for supporting the NICs on a blade server are not part of a standard
Windows 2000 install, and the NICs will be generically listed in Windows 2000 Device
Manager as two or more
Ethernet Controllers (with a question mark next to them) until the
necessary drivers are loaded. For these NICs to become active, a third-party driver, supplied
by IBM, must be installed. The
normal procedure most users follow is to install the drivers on
the first Ethernet Controller in the list, and then install the drivers on the second Ethernet
Controller in the list (and so on). The end result of this is the
most-cases scenario previously
mentioned, where the Windows 2000 connection named Local Area Connection goes to
CIGESM1 and the one named Local Area Connection 2 goes to CIGESM2.
If, however, the drivers are installed on the second Ethernet Controller in the list first, and then
the first Ethernet Controller in the list, the connection names are reversed, and the connection
named Local Area Connection is now the one going to CIGESM2, and the connection named
Local Area Connection 2 is now going to CIGESM1.
For W2K3 there is a native Broadcom driver that may or may not load up in what might be
perceived as a logical fashion. One might see Local Area Connection going to the top or the
bottom NIC, with Local Area Connection 2 going to the other physical NIC.
For Linux, the default eth0 goes to the Cisco Systems IGESM in switch bay 2 (CIGESM2 in
the examples in chapter 7) and eth1 goes to the Cisco Systems IGESM in switch bay 1
(CIGESM1 in the examples in chapter 7). Note that this is reversed from a
normal Windows
2000 install, as previously mentioned, and can be affected by the order drivers are installed.
Default gateway configuration on multihomed servers
Most blade servers (HS20/JS20) in the BladeCenter by default have two connections to the
network, each usually on separate IP subnets. Using the Broadcom teaming software
enables you to increase the number of subnets configured on a blade server above and
beyond that available on the physical connections. The end result is that the blade server
frequently has more than a single IP subnet configured.
One question that frequently comes up: Should each IP subnet configured on a multihomed
system, such as the blade server, have a default gateway assigned? The answer is far from
straightforward.
For all examples in this chapter, only one interface receives a default gateway, and the other
interfaces are left blank for the default gateway field. This is not to suggest that this is the best
Important: To avoid confusion, always install drivers sequentially, from the first Ethernet
Controller in the list to the last Ethernet Controller in the list.
Important: As an aid to figuring out which logical NIC is going to which physical IGESM,
you can Telnet to the top IGESM and shut down the interface on the top IGESM going to
the blade server in question. Because of this shutdown on the IGESM side, one of its
connections on the blade server side will be reported as down. Whichever one is reported
as down will be the one physically attached to the top IGESM, regardless of the logical
name the operating system has assigned it.
Using the inverse of this procedure (from the OS, disabling one of the NICs, then going into
each IGESM and seeing which port goes down), might be valid, as disabling the port on
the blade server side may or may not result in the port on the IGESM side going down due
to the nature of the physical interface on the blade server. Based on this, the first method is
the recommended way to determine logical-to-physical link connectivity.